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BrainWave: A Matlab Toolbox for Beamformer Source Analysis of MEG Data

Cecilia Jobst, Paul Ferrari, Silvia Isabella, Douglas Cheyne
2018 Frontiers in Neuroscience  
two different types of source reconstruction implemented in the BrainWave toolbox: (1) event-related beamforming of averaged brain responses and (2) beamformer analysis of modulation of rhythmic brain  ...  This article provides an overview of the main features of BrainWave with a step-by-step demonstration of how to proceed from raw experimental data to group source images and time series analyses.  ...  Thresholding Using Permutation Tests To statistically threshold source images, BrainWave includes a simple non-parametric permutation test (Nichols and Holmes, 2002; Chau et al., 2004; Lin et al., 2006  ... 
doi:10.3389/fnins.2018.00587 pmid:30186107 pmcid:PMC6113377 fatcat:3v4p6oa55vberb7adt7epvlusi

Oscillatory neuronal dynamics associated with manual acupuncture: a magnetoencephalography study using beamforming analysis

Aziz U. R. Asghar, Robyn L. Johnson, William Woods, Gary G. R. Green, George Lewith, Hugh MacPherson
2012 Frontiers in Human Neuroscience  
Magnetoencephalography (MEG) enables non-invasive recording of neuronal activity, with reconstruction methods providing estimates of underlying brain source locations and oscillatory dynamics from externally  ...  In a beamformer analysis, a two-minute period of manual acupuncture needle manipulation delivered to the ipsilateral right LI-4 (Hegu) acupoint was contrasted with a two-minute baseline period.  ...  We thank Dr Mark Lythgoe, UCL Institute of Child Health, University College London, for his helpful advice and suggestions.  ... 
doi:10.3389/fnhum.2012.00303 pmid:23248594 pmcid:PMC3522113 fatcat:he2btj64mzeebnssa6b32wxp3i

Spatiotemporal oscillatory dynamics during the encoding and maintenance phases of a visual working memory task

Elizabeth Heinrichs-Graham, Tony W. Wilson
2015 Cortex  
In this study, we examined the oscillatory dynamics that serve visual working memory operations using high-density magnetoencephalography (MEG) and advanced time-frequency and beamforming methodology.  ...  found that theta (4-7 Hz) activity in the frontal cortices parametrically increased as a function of memory load during the memory maintenance  ...  The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.  ... 
doi:10.1016/j.cortex.2015.04.022 pmid:26043156 pmcid:PMC4522359 fatcat:45ljb5nxdrab5hrbvzevi4tevy

Quiet connections: Reduced fronto-temporal connectivity in nondemented Parkinson's Disease during working memory encoding

Alex I. Wiesman, Elizabeth Heinrichs-Graham, Timothy J. McDermott, Pamela M. Santamaria, Howard E. Gendelman, Tony W. Wilson
2016 Human Brain Mapping  
All data were transformed into the time-frequency domain and significant oscillatory activity was imaged using a beamforming approach.  ...  Each participant completed a high-load, Sternberg-type working memory task during magnetoencephalography (MEG), and we focused on the encoding and maintenance phases.  ...  The Center for Magnetoencephalography at the University of Nebraska Medical Center was founded by the generosity of an anonymous donor.  ... 
doi:10.1002/hbm.23237 pmid:27151624 pmcid:PMC4980162 fatcat:dwl6xiw4mbeu5gzatm6dsodiza

Identifying true cortical interactions in MEG using the nulling beamformer

Hua Brian Hui, Dimitrios Pantazis, Steven L. Bressler, Richard M. Leahy
2010 NeuroImage  
We estimate interaction measures from the output of the modified beamformer and test for statistical significance using permutation tests.  ...  of our nulling beamforming method.  ...  Acknowledgments This work was supported by National Institute of Biomedical Imaging and BioEngineering under Grants No R01-EB002010 and No R01-EB000473.  ... 
doi:10.1016/j.neuroimage.2009.10.078 pmid:19896541 pmcid:PMC2818446 fatcat:p2iyrzulbjelffkeqk4o6pdhba

Circadian modulation of motor-related beta oscillatory responses

Tony W. Wilson, Elizabeth Heinrichs-Graham, Katherine M. Becker
2014 NeuroImage  
All MEG data were corrected for head motion and examined in the time-frequency domain using beamforming methods.  ...  Finally, beta levels during the baseline period also increased from 09:00 to 16:00 in most regions of the cortical sensorimotor network.  ...  The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.  ... 
doi:10.1016/j.neuroimage.2014.08.013 pmid:25128712 pmcid:PMC4252760 fatcat:mc76x4lfkbf7veyrkxowsykete

Population-level inferences for distributed MEG source localization under multiple constraints: Application to face-evoked fields

R.N. Henson, J. Mattout, K.D. Singh, G.R. Barnes, A. Hillebrand, K. Friston
2007 NeuroImage  
We compared the face validity of subject-specific forward models and their summary statistics in terms of how estimated responses reproduced over subjects.  ...  We used these to compare different summary statistics, namely; (i) whether to test for differences between condition-specific source estimates, or whether to test the source estimate of differences between  ...  Nonetheless, we repeated the group analyses using non-parametric permutation tests, as implemented in SnPM (Nichols and Holmes, 2002) , with a threshold corrected for multiple comparisons using family-wise  ... 
doi:10.1016/j.neuroimage.2007.07.026 pmid:17888687 fatcat:zl4nioeoxrey7comjgx7qgbyd4

Aberrant Neuronal Dynamics during Working Memory Operations in the Aging HIV-Infected Brain

Tony W. Wilson, Amy L. Proskovec, Elizabeth Heinrichs-Graham, Jennifer O'Neill, Kevin R. Robertson, Howard S. Fox, Susan Swindells
2017 Scientific Reports  
Significant oscillatory neural responses were imaged using a beamforming approach to illuminate the spatiotemporal dynamics of neuronal activity.  ...  HIV-infected older adults and a demographically-matched group of uninfected controls performed a verbal working memory task during magnetoencephalography (MEG).  ...  The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.  ... 
doi:10.1038/srep41568 pmid:28155864 pmcid:PMC5290733 fatcat:aztvl3efsjexta2n7m56jyfsyq

A direct relationship between oscillatory subthalamic nucleus–cortex coupling and rest tremor in Parkinson's disease

Jan Hirschmann, Christian J. Hartmann, Markus Butz, Nienke Hoogenboom, Tolga E. Özkurt, Saskia Elben, Jan Vesper, Lars Wojtecki, Alfons Schnitzler
2013 Brain  
Tremor-associated changes in cerebro-muscular coherence were localized by Dynamic Imaging of Coherent Sources.  ...  Abbreviations: DBS = deep brain stimulation; ImCoh = imaginary part of coherency; LFP = local field potential; MEG = magnetoencephalography 3660 | Brain 2013: 136; 3659-3670 J.  ...  Furthermore, we are very thankful to Medtronic for providing non-magnetic lead extensions. In addition, we thank Mrs. E. Rä disch for assistance with MRI scans.  ... 
doi:10.1093/brain/awt271 pmid:24154618 fatcat:y6mn22q6ybauljmckgvdcanzg4

A new approach to neuroimaging with magnetoencephalography

Arjan Hillebrand, Krish D. Singh, Ian E. Holliday, Paul L. Furlong, Gareth R. Barnes
2005 Human Brain Mapping  
We discuss the application of beamforming techniques to the field of magnetoencephalography (MEG).  ...  What is more, MEG beamformer analysis facilitates the study of these complex interactions within cortical networks that are involved in both sensory-motor and cognitive processes.  ...  The effects of non-stationarities in the MEG signals on the estimate of the data covariance matrix, and therefore the beamformer images, have yet to be studied.  ... 
doi:10.1002/hbm.20102 pmid:15846771 fatcat:xej6cd5manc6va2tkujqi4s64y

Abnormal MEG Oscillatory Activity during Visual Processing in the Prefrontal Cortices and Frontal Eye-Fields of the Aging HIV Brain

Tony W. Wilson, Howard S. Fox, Kevin R. Robertson, Uriel Sandkovsky, Jennifer O'Neill, Elizabeth Heinrichs-Graham, Nichole L. Knott, Susan Swindells, Satoru Hayasaka
2013 PLoS ONE  
All MEG data was imaged in the time-frequency domain using beamforming.  ...  Despite a large body of neuroscience and imaging studies, the pathophysiology of these HIV-associated neurocognitive disorders (HAND) remains unresolved.  ...  Briefly, statistical parametric maps were thresholded at (p,0.01) to define clusters of potentially significant activation.  ... 
doi:10.1371/journal.pone.0066241 pmid:23840428 pmcid:PMC3688779 fatcat:l2hkqqiplfhizdcfncaezxttv4

Concordance between the Wada test and neuroimaging lateralization: Influence of imaging modality (fMRI and MEG) and patient experience

Steven Kemp, Garreth Prendergast, Theodoros Karapanagiotidis, Gus Baker, Thomas P. Kelly, Tufail Patankar, Simon S. Keller
2018 Epilepsy & Behavior  
Concordance rates (N=16) were non-significant (Cohen's Kappa) between fMRI and Wada test (memory) and between MEG and Wada test (memory and language).  ...  Sixteen (84%) patients who were scanned reported some level of obtundation in MEG.  ...  We are very grateful to the 19 patients that gave us 1 full-day of their time to undergo further brain scans.  ... 
doi:10.1016/j.yebeh.2017.09.027 pmid:29245083 fatcat:fpv6pazntjfg3psotycf55incq

Friends, not foes: Magnetoencephalography as a tool to uncover brain dynamics during transcranial alternating current stimulation

Toralf Neuling, Philipp Ruhnau, Marco Fuscà, Gianpaolo Demarchi, Christoph S. Herrmann, Nathan Weisz
2015 NeuroImage  
By means of application of beamforming to magnetoencephalography (MEG) data, we successfully recovered modulations of the amplitude of brain oscillations during weak and strong tACS.  ...  Future tACS experiments will be able to deliver direct physiological insights in order to further the understanding of the contribution of brain oscillations to cognition and behavior.  ...  T.N. was further supported by a stipend of the Lienert Stiftung.  ... 
doi:10.1016/j.neuroimage.2015.06.026 pmid:26080310 pmcid:PMC4686537 fatcat:lcox2f2pxzhfhgwshewqczbz4y

Presence of strong harmonics during visual entrainment: A magnetoencephalography study

Elizabeth Heinrichs-Graham, Tony W. Wilson
2012 Biological Psychology  
We utilized magnetoencephalography (MEG) to examine synchronization at harmonics of the visual stimulation frequency (18 Hz).  ...  MEG data were analyzed for eventrelated-synchronization (ERS) at the fundamental frequency, 36, 54, and 72 Hz. We found strong ERS in all bands.  ...  Rojas and Eugene Kronberg at the University of Colorado Denver School of Medicine.  ... 
doi:10.1016/j.biopsycho.2012.04.008 pmid:22569101 pmcid:PMC3407313 fatcat:l6draalwlfh5fkci627ahvi5eu

Aberrant high-frequency desynchronization of cerebellar cortices in early-onset psychosis

Tony W. Wilson, Erin Slason, Olivia O. Hernandez, Ryan Asherin, Martin L. Reite, Peter D. Teale, Donald C. Rojas
2009 Psychiatry Research : Neuroimaging  
task effects using statistical parametric mapping.  ...  MEG data were imaged in the frequencydomain, using spatial filtering, and the resulting event-related synchronizations and desynchronizations (ERS/ERD) were subjected to voxel-wise analyses of group and  ...  Acknowledgments This work was supported by grants from the National Institute of Mental Health (R01 MH63442-02), and the Developmental Psychobiology Research Group (DPRG) of the University of Colorado  ... 
doi:10.1016/j.pscychresns.2009.03.009 pmid:19783411 pmcid:PMC2760661 fatcat:nrijluoazvbedf7f5yecyzcqum
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